BUILD: log: unused variable svid

This results from previous fix.
CLEANUP: http: rename the misleading http_check_access_rule

Several bugs were introduced recently due to a misunderstanding of how
this function works and what it was supposed to do. Since it's supposed
to only return the pointer to a rule which aborts further processing of
the request, let's rename it to avoid further issues.

The function was also slightly cleaned up without any functional change.
MINOR: http: move redirect rule processing to its own function

We now have http_apply_redirect_rule() which does all the redirect-specific
job instead of having this inside http_process_req_common().

Also one of the benefit gained from uniformizing this code is that both
keep-alive and close response do emit the PR-- flags. The fix for the
flags could probably be backported to 1.4 though it's very minor.

The previous function http_perform_redirect() was becoming confusing
so it was renamed http_perform_server_redirect() since it only applies
to server-based redirection.
REORG: config: move the http redirect rule parser to proto_http.c

We'll have to use this elsewhere soon, let's move it to the proper
place.
MEDIUM: http: add support for "http-request redirect" rules

These are exactly the same as the classic redirect rules except
that they can be interleaved with other http-request rules for
more flexibility.

The redirect parser should probably be changed to stop at the condition
so that the caller puts its own condition pointer. At the moment, the
redirect rule and condition are parsed at once by build_redirect_rule()
and the condition is assigned to the http_req_rule.
MEDIUM: http: add support for "http-request tarpit" rule

The "reqtarpit" rule is not very handy to use. Now that we have more
flexibility with "http-request", let's finally make the tarpit rules
usable there.

There are still semantical differences between apply_filters_to_request()
and http_req_get_intercept_rule() because the former updates the counters
while the latter does not. So we currently have almost similar code leafs
for similar conditions, but this should be cleaned up later.
MINOR: ssl: Setting global tune.ssl.cachesize value to 0 disables SSL session cache.
[RELEASE] Released version 1.5-dev17

Released version 1.5-dev17 with the following main changes :
    - MINOR: ssl: Setting global tune.ssl.cachesize value to 0 disables SSL session cache.
    - BUG/MEDIUM: stats: fix stats page regression introduced by commit 20b0de5
    - BUG/MINOR: stats: last fix was still wrong
    - BUG/MINOR: stats: http-request rules still don't cope with stats
    - BUG/MINOR: http: http-request add-header emits a corrupted header
    - BUG/MEDIUM: stats: disable request analyser when processing POST or HEAD
    - BUG/MINOR: log: make log-format, unique-id-format and add-header more independant
    - BUILD: log: unused variable svid
    - CLEANUP: http: rename the misleading http_check_access_rule
    - MINOR: http: move redirect rule processing to its own function
    - REORG: config: move the http redirect rule parser to proto_http.c
    - MEDIUM: http: add support for "http-request redirect" rules
    - MEDIUM: http: add support for "http-request tarpit" rule